Process of generating producer-gas.



4 Sheds-Sheet i.

- Patented Dec. 9; 1902.

m. VAN B. smm. PBDGESS 0F GENERATING PRODUCER GAS.

(Application filed NW- 18, 1901.)

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(llo Model.)

i Inventor Attorneys w 4 I Guru.

Witngsses:

No. 75,3". Patented Dec. 9, I902.

M. VAN B. SMITH.

PROCESS OF GENEBAT'NG PRODUCER GAS.

(A umion'med Nov. 18, 1901.)

(No M04161.) 4 Sheets-Sheet 2,

Witnesses: lnvenfdr m: NORRIS PETERS c0, mom-um" WhSHiHGfOS. q. a

No. 715,3. Patented Dec. 9, I902.

M. VAN B. SNHTH.

PROCESS OF GENERATING PRODUCER GAS.

(Application filed Nov. 18, 1901.)

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7 i g n%%mfi%% I j 8 Patented Dec. 9, I902. 11. VAN B. SMITH. PROCESS OFGENERATING PRODUCER GAS.

(Applied-inn Med Nov 18, 1901.)

4 Sheets-Sheet 4.

(No Model.)

Attorneys QZAZEZE UNITED STATES PATENT OFFICE.

MARTIN VAN BUREN SMITH, OF NEW YORK, N. Y., ASSIGNOR TO THE AMERICANSTOKER COMPANY, OF NEW YORK, N. Y., A CORPORA- TION OF NEW YORK.

PROCESS OF GENERATING PRODUCER-GAS.

SPECIFICATION forming part of Letters Patent No. '71 5,311, datedDecember 9, 1 902. Application filed November 18,1901. Serial No.82,665. o specimens-l To all whom it may concern:

Be it known that I, MARTIN VAN BUREN SMITH, a citizen of the UnitedStates, residing in the borough of Manhattan, in the city, county, andState of New York, have invented a certain new and useful Process ofGenerating Producer-Gas, of which the following is a description.

In an application for Letters Patent filed November 28, 1898, Serial No.697,235, I describe an apparatus for generating producergas, whereingreen fuel is introduced into a body of incandescent coke from below inthe presence of a limited air-supply, insufficient to produce combustionof the gas, the resulting ash being continuously withdrawn from,

the apparatus through water-sealed ash-pits below the body ofincandescent fuel. My present application is designed to cover theprocess involved in the operation of apparatus of this type, either ofthe specific form de scribed and claimed in said application orequivalent apparatus designed to perform substantially the sameoperations.

My object is to provide. a simple and efficient process for thegeneration of producergas and by which a practically stable gas will begenerated in the first instance and which will not be contaminated withunstable constituents which require to be removed by subsequentpurifying processes.

In the accompanying drawings I illustrate an apparatus of the typedescribed by me in my said application and which is entirely suitablefor the carrying on of my present method.

In the drawings, Figure 1 is a cross-section through the generator,taken on. the line 1 1 of Fig. 4; Fig. 2, a cross-section through theunderfeed-stoker, showing the same in enlarged view and in detail; Fig.8, a longitudinal section on the line 3 3 of Figs. 1 and 4; Fig. 4, across-section on the line 4 a of Fig. 1; Fig. 5, an enlarged detail ofone of the nozzles shown in Fig. 4 and through which air and steam areintroduced into the generating-chamber; Fig. 6, a section through thegenerator on the line 6 6 of Fig. 1, and Fig. 7 a top view of thegenerator.

parts are represented by the same numerals of reference.

Up to the present time it has been the common practice in the operationof generators of producer-gas to apply the fresh or green fuel on top ofthe incandescent coke, and as a consequence the gases generated arecharged with water expelled from the green coal and frequently also withvaporized liquid hydrocarbons, such as tar. These additionalconstituents make the producergas unstable, and it is therefore thepractice at the present time to remove them by subsequent purifyingprocesses when a stable gas is desired. One

of the principal features of my present invention consists in reversingthis practice by the introduction of the green fuel below theincandescent body of coke instead of above it. The result of this changeis marked. In the first place the water expelled from the green fuel inpassing up through the incandescent body of cokeis converted intohydrogen and carbonicoxid gases, which are stable. In the second placethe liquid hydrocarbons are oxidized and also converted into hydrogenand carbonic-oxid gases. In the third place, since the distillation ofthe hydrocarbons takes place in a zone in which free oxygen is present,theyare decomposed and converted into carbonic-acid gas,which in itspassage through the incandescent coke on its way to the exitflue isconverted into carbonic-oxid gas in precisely the same way that thecarbonic-acid gas resulting from the combustion of the coke is on itsway to the flue converted into carbouic-oxid gas. As a result, the gasproduced is more nearly pure carbonic-oxid and hydrogen gases, free frommoisture and volatilized liquid hydrocarbons, and therefore a stable gasgenerated as such and not made stable by any subsequent process, such aswashing or scrubbing or draining olf of the non-stable and depositedconstituents. Va-

rious diiiiculties arising from the unstability of producer-gas as nowmade are therefore avoided, and a gas which is suitable for generalheating purposes is produced. In the manufacture of such gas I prefer tointroduce steam, as it is the common practice to do in the manufactureof producer-gas, to supplement the combustible gases produced.

The following is a description of the structure shown in theaccompanying drawings:

1 1 are the Walls of the furnace, which are contracted near the bottom,as shown.

2 2 are suitable hoppers arranged on top of the furnace, through whichthe initial charge of fuel is introduced. These hoppers are providedwith weighted doors 3.

4 4C are the uptakes leading to the gasmain 5.

6 is a conduit leading toa regenerative furnace or other device forutilizing the gasproduced in the generator.

7 7 are devices for introducing the fuel under the bed of incandescentcoke contained in the generator-chamber. These devices are shown as anunderfeed-stoker, in which the coal is fed from the hopper by means ofan Archimedes screw and is by said screw elevated into thegas-generating chamber.

8 8 are steam-pipes, and 9 9 are air-openings, the parts being assembledand arranged so that the issuing steam forces into the lower part of thegenerating-chamber commingled air and steam.

The underfeed-stoker is shown in detail in Fig. 2, in which 10 is theArchimedes screw; 11, the coal-reservoir; 12, an air-chamberprovidedwith a forced draft. 13 13 are twyerblocks, and la 14 are openings fromwhich air is ejected. These stokers, as shown in Fig. 3, may be arrangedend to end and placed at or near the pinnacle of a central abutment 15,located so as to discharge the green fuel above the point where the airand steam enter through the nozzles 8 9. 16 16 are watersealed ash-pits,into which the incombustible ash or residue descends.

The operation of the device shown in the drawings may thus be described:Through the hoppers 2 2 on starting the generator kindlings are firstintroduced, and on top of them coke is introduced to the desired depth.The fire being lighted and the coke brought to the required condition ofincandescence, the stokers are started, and green coal is continuouslyfed into the generator under the incandescent coke. This fuel as it isfed upward is converted into coke by the distillation of its hydrocarbonconstituents, (solid and liquid,) which in the presence of the airissuing through the twyer-openings are decomposed, forming carbonic-acidgas (which passing upward through the incandescent body of coke above itis converted into carbonic-oxid gas before it leaves the generator) andhydrogen. The water contained in the coal is, like the steam introducedthrough the nozzle 8, decomposed, producing hydrogen gas. The fresh cokeoverflows from the stoker and passes down at the sides of the abutmenton which it is located, where it meets the incoming air and steamintroduced through the nozzles 89. In the presence of the free oxygen(and perhaps aided by the oxygen of the steam) combustion of the cokeensues and carbonic-acid gas is produced, which passing upward throughthe incandescent body of coke above it is converted into carbouic-oxidgas. The hydrogen which results from the decomposition of the steampasses up through the incandescent coke unchanged. As a result a newindustrial gas is formed,which differs from ordinary producergas in thatit is practically free from water, tar, and other unstable constituentsand in which a portion at least of the hydrocarbon has been convertedinto carbonic-oxid gas by combustion and subsequent carbonization, itbeing understood that carbonic acid in its passage through theincandescent body of coke takes up carbon and is converted intocarbonic-oxid gas.

It will of course be understood that in the practice of my process anymeans whereby the green fuel is introduced under the incandescent bodyof coke may be employed and that, furthermore, myinvention in itsbroader aspects is not limited to the use of a stoker of theconstruction shown or of any particular construction, the advantage ofthis feature of the apparatus described being that a continuous anduniform feed of fuel is as sured with the minimum labor. Although I nowprefer to use separate nozzles 8 9 for the introduction of air and steamto effect the combustion of the coke, the passages through the twyers ofthe stoker may be relied upon for the introduction of all theatmospheric air required in the operation, and, in addition, steam maybe introduced by way of these openings. In any event the introduction ofsteam may be omitted altogether, although it is universally recognizedas good practice to introduce so much steam as can be decomposed withoutreducing the temperature within the generator below the required point.

When I speak of the incandescent body of coke being above thefreshly-introduced fuel, it will be understood that the same resultwould be attained if the coal were introduced above the coke and theexit-pipe were below it. In other words, the incandescent coke is tointervene between the freshly-introduced fuel and the exit-pipe from thegenerator.

Instead of distilling the hydrocarbons in the presence of free oxygen orcommingling them with free oxygen before they leave the generator orretort, thus causing combustion, the coal might be introduced above thezone of free oxygen where combustion would not take place. In theapparatus shown in the drawings, this might, for example, be done byomitting the air-openings 14 14 in the twyer-blocks. The resulting gasin this case would contain a larger proportion of hydrocarbon gas; butthe water in the coal would still be converted into hydrogen gas duringits passage through the incandescent coke.

Having now described my invention, what I claim as new, and desire tosecure by Letters Patent, is as follows:

1. The method of generating producer-gas from coal, which consists inmaintaining a volume of incandescent fuel from which free air isexcluded, in injecting into the incandescent fuel two columns of airinsufficient in volume to support complete combustion, and in feedingbelow the volume of fuel and between the injected air a continuoussupply of green or fresh fuel, as and for the purposes set forth.

2. The method of generating producer-gas from coal, which consists inmaintaining a volume-of incandescent fuel from which free air isexcluded, in injecting into the incandescent fuel two columns of airinsufiicient in volume to support complete combustion, in feeding belowthe volume of fuel and between the injected air a continuous supply ofgreen or fresh fuel, and in continuously withdrawing the resulting ashformed by the combustion, as and for the purposes set forth.

3. The method of generating producer-gas from coal, which consists inmaintaining a volume of incandescent fuel from which free air isexcluded, in feeding below the Volume of fuel a continuous supply ofgreen or fresh fuel with an insufficient supply of air to supportcomplete combustion, and in introducing below the combustion-zone of theburning fuel an additional supply of air, as and for the purposes setforth.

4. The method of generating producer-gas from coal, which consists inmaintaining a volume of incandescent fuel from which free air isexcluded, in feeding below the volume of fuel a continuous supply ofgreen or fresh fuel with an insufficient supply of air to supportcomplete combustion, and in introducing below the combustion zone of theburning fuel an additional supply ofair and steam, as and for thepurposes set forth.

This specification signed and witnessed this 30th day of October, 1901.

MARTIN VAN BUREN SMITH.

\Vitnesses:

FRANK L. DYER, JNo. R0131. TAYLOR.

